Hide Layer with Checkbox in After Effects

How to hide a layer with a checkbox in After Effects?

1. Add Checkbox Control to your layer and rename it to Show layer.
2. Alt-click on the Opacity property and paste the expression below.

effect("Show layer")("ADBE Checkbox Control-0001") * 100;

How does it work?
The checkbox control has to 2 possible values on and off which are equal 1 and 0. If you link opacity to a checkbox with a pick whip it will be equal 1 or 0. We multiply both values by 100 and get 100 (1×100) or 0 (0x100) instead.

Where can I use it?
This technique is widely used in After Effects templates, it helps other people to work faster with your project.